Water trip switch



March 18, 1952 A. v. HUGHES ErAL WATER TRIP SWITCH 2 SHEETS-SHEET l Filed April 18, 1946 I l l INVENTORS /r/w I/ages w74/ an/rence Wade/naaien WITNESSES:

ATTOR N EY March 18, 1952 A. v. HUGHESl ET AL WATER TRIP SWITCH 2 SHEETS-SHEET 2 Filed April 18, 1946 r l l INVENToRs r/a/ //g//es afm aw/e//eBlY fade/vaciar.

Mr, @M/M A ATTORNEY WITNESSES:

Patented Mar. i8, 1952 WATER TRIP SWITCH Arthur V. Hughes and Lawrence B. Rademacher, Sharon, Pa., assignors, by mesne assignments, to the United States of America as represented by the Secretary of the Navy Application April 18, 1946, Serial No. 663,204

(Cl. 20o-52) 11 Claims.

Our invention relates to switches and, more particularly, to trip switches of special utility for controlling the propulsion equipment and other equipment on torpedoes, or hydro-bombs.

Modern warfare has introduced the aerial torpedo as well as the torpedo that is launched from small service boats not carrying ring tubes. These types of torpedoes may be propelled electrically or by means of a jet motor. With such torpedoes, it is important that the propulsion equipment be set in operation only after the torpedo is free of the launching craft and is in the sea.

It is a broad object of our invention to provide a water trip switch actuated by the flow of the water past the torpedo on striking the sea.

Another object of our invention is the provision of a water trip switch for a torpedo actuated by the flow of water relative to the torpedo and the provision of sealing means for effectively sealing the interior of the torpedo from the sea water outside of the torpedo.

Another and somewhat more specic Object of our invention is the provision of a water trip switch operable by the sea water and mounted on a hand hole cover so as to provide a unitary structure that may be readily mounted in the torpedo and removed therefrom.

Another object of our invention is the provision of a water trip switch that is inexpensive, simple, and above all reliable under the operating conditions imposed on it. The objects hereinbefore expressly made are merely illustrative of many other objects of our invention, which other objects and advantages will become more readily apparent from a study of the following specication and the accompanying drawings, in which:

Figure 1 is a plan view of our water trip switch shown as a unitary structure with a hand hole cover;

Fig. 2 is side view shown in Fig. l;

Fig. 3 is a view in transverse section of our water trip switch, the section being taken on section line III-III shown in Fig. 2; and

Fig. 4 is a front View of our water trip switch.

Numeral l designates the shell or housing of the torpedo to which, at a suitable region for a handhole aft of the forward mounting ring of the jet motor (not shown) for the torpedo, a ring 2 is hermetically welded to the shell I. The ring 2 has a seating surface 3 for the cover A. The seating surface is provided with an annular of the subject matter groove 5 for receiving the gasket 6. The handhole cover I is provided with an annular projection 8 to coact with the gasket 6 to form a liquid-tight seal when the hand-hole cover is bolted in place by the bolts 'I.

The hand-hole cover 4 is provided with a well having parallel side walls 9 and I0. The side wall I is provided with a relatively large opening so that the bearing I I, the liquid seal I2 and shaft I3 may be inserted from the left as seen in Fig. 3. The shaft I3 is provided with a splined region at the right to snugly t into a mating sleeve I4 at the bottom of the vane I5. The right end of shaft I3 fits in to a bearing recess in side wall 9. After the shaft I3 and associated elements are positioned in the side walls 9 and IU as shown, the retaining nut I is screwed into place and is then locked in position by the lock screw I1.

A switch actuating arm I8 is rigidly secured to the shaft I3 at the left. The relative connection f, of arm I 8 and vane I5 to the shaft I3 is such that when the vane is in vertical position the arm I8 is in the position shown in full line in Fig. 2.

The arm I8 is provided with a pin I9 and a pin 20 is so secured to the side wall IIJ that the tension force of the spring 2l lies a short distance above the axis of the shaft I3. The arm I8 and thus the vane I 5 are thereby biased to counter-clockwise rotation. The vane I5 is provided with a stop button 22 engaging the forward end Wall of the well to thus limitthe counter-clockwise rotation of the vane. It is thus apparent that the forward end wall of the well acts as a stop for the counter-clockwise rotation of vane I5, and this is so whether the stop button 22 is used or not. A frangible wire, or cord, 23, is looped as shown through a hole in the button 22 anda hole in the cover to hold the vane I5 in the position shown. The purpose of this feature will become more apparent from the discussion to follow.

The arm I8 carries a plurality of contact bridg ing elements 24 disposed for coaction with corresponding switch contacts mounted on the bar 26 secured to the cover as shown.

Just aft of the vane I5, we dispose the latch block 2l. This latch lblock 2! is so shaped at the aft end to nt into the corner 23 in the well. The block carries a spring 29 for biasing the plunger inthe forward direction. The plunger 3Q has a spherically shaped forward end to fit into a mating recess in the aft face of the vane I5. The vane I5, when no switching operation is desired. is thus rmly held or latched in the position shown. The block 21 is provided with a suitable eye 3l into which a lanyard 32 is secured.

Our switch is to operate only after the torpedo strikes the water. A discussion of the operation of the elements described will thus bring out this function.

When the torpedo, or hydro-bomb is released from the launching plane, the lanyard 32, which is secured to the block 2'! and to the plane structure, after the torpedo has dropped the length of the lanyard, will snap the block from the position shown. The vane I5 is thus deprived of its aft back-up structure and thus becomes unlatched. Since it is important that the force of the air, during the rather rapid forward movement and descent of the torpedo, do not operate the water trip switch two safety features are provided. The tension force of the over-center spring 2! in relation to the shaft axis of shaft I3 and the location of pins I9 and 2G is so chosen that the spring force is sufcient to prevent the vane I5 from being actuated in the clockwise direction by the force of the air. Further, the strength of wire 23 is so chosen that the force of the air will not actuate the vane.

When the torpedo strikes the water, the force of the Water on vane I5 will be several times the combined retaining force of the spring 2| and wire 23. The wireY is thus broken and the vane I5 is thus moved clockwise moving the spring to the over-center position. The switch contacts 24 and 25 are thus brought into engagement with a snap action.

Since the spring action of spring 2i continues the contacts 24 and 25 remain in firm engagement. The vane I5 moves into the corner 28 to thus be flush with the torpedo shell. The vane l 5 thus oers no further resistance to the torpedo movement nor will anything in the sea catch on the vane. The closure of the switch contacts 24 and 25 thus sets up the necessary circuits to start the propulsion equipment and other apparatus in the torpedo.

It will be noted that arm I8 appears to be longer than necessary. Since our switch is of particular utility with a jet propelled torpedo and since the jet motor is a rather dangerous piece of equipment, the elongated arm I8 prevents mounting of the jet motor except when the water trip switch elements are in the position shown in full line.

While we have shown but one embodiment, we do not wish to be limited to the particular show- Ving made but Wish to be limited only by the scope of the claims hereto appended.

We claim as our invention:

1. An electric switch, comprising, in combination, a leakproof housing forming a barrier for preventing movement of the medium outside of the housing to the inside, said housing in normal use being launched into the sea at relatively high speed and from a given altitude, a leakproof bearing in said barrier, an oiset bell-crank lever having one arm disposed at the outside of the barrier, a shaft portion in the bearing, and anotherarm at the inside of the barrier, an' overcenter spring assembly for biasing the bell-crank lever to a given end position, a vane on the arm outside of the housing for operating the bellcrank lever by the flow of the sea water past the housing as the housing strikes the sea, means for latching said bell-crank lever into said end position, and means operable by the launching of said housing for unlatching said bell-crank lever, said over-center spring assembly being so selected that the force of the air on the vane is not sufcient to operate the bell-crank lever during the period elapsing between the moment the bell-crank lever is unlatched and the moment the housing strikes the sea.

2. An electric switch, comprising, in combination, a leakproof housing forming a barrier for preventing movement of the medium outside of the housing to the inside, said housing in normal use being launched into the sea at relatively high speed and from a given altitude, a leakproof bearing in said barrier, an offset bell-crank lever having one arm disposed at the outside of the barrier, a shaft portion in the bearing, and another arm at the inside of the barrier, an overcenter spring assembly for biasing the bell-crank lever to a given end position, a vane on the arm outside of the housing for operating the bellcrank lever by the flow of the sea water past the housing as the housing strikes the sea, means for latching said bell-crank lever into said end position, means operable by the launching of said housing for unlatching said bell-crank lever, said over-center spring assembly being so selected that the force of the air on the vane is not sufficient to operate the bell-crank lever during the period elapsing between the moment the bell-crank lever is unlatched and the moment the housing strikes the sea, and a frangible coupling for securing said bell-crank lever in said end position, but which coupling is broken by the impact of the sea water against the vane.

3. An electric switch, comprising, in combination, a barrier for preventing leakage of the medium at one side of the barrier to the other side, a leakproof bearing in said barrier, an olfset bell-crank lever having one arm disposed at one side of the barrier and the other arm at the other side of the barrier, a shaft portion in the bearing, switching means on one arm, a vane on the other arm to be actuated by the ow of the medium past the vane, an over-center spring assembly for holding the bell-crank lever in one position till the force of the medium on the vane exceeds a given value, means for locking said vane in a given position, said last named means being operable to unlock said vane under given operating conditions whereby said vane is free to operate said bell-crank lever to actuate said switching means, and switching means stationary with reference to the barrier disposed to be engaged by the switching means on one of saidarms.

4. An electric switch disposed in a housing which in normal use is launched from a craft into the sea from a selected altitude while moving through the atmosphere at a considerable speed, in combination, a bell-crank lever pivoted in the housing so that one armprojects from the housing and the other is disposed in the housing, a stop on the housing, an over-center spring assembly for holding the lever in one end position against the stop, said over-center spring assembly providing a suicient biasing force that the force of the air on the arm projecting from the housing is not sufficient to actuate the lever but having a biasing force that is far insufficient to prevent operation of the lever by the impact of the sea water against the lever projecting from the housing when the housing strikes the sea, and switching means operated by the operation of the lever.

5. An electric switch disposed in a housing which in normal' use is launched from a craft into the sea from a selected altitude while moving through the atmosphere at a considerable speed, in combination, a bell-crank lever pivoted in the housing so that one arm projects from the housing and the other is disposed in the housing, a stop on the housing, an over-center spring assembly for holding the lever in one end position against the stop, said over-center spring assembly providing a sufficient biasing force that the force of the air on the arm projecting from the housing is not sufficient to actuate the lever but having a biasing force that is far insufficient to prevent operation of the lever by the impact of the sea water against the lever projecting from the housing when the housing strikes the sea, and switching means operated by the operation of the lever, a breakable coupling between the housing and lever for holding the lever against the stop but which breaks when the housing strikes the sea and the sea water acts on the arm projecting from the housing.

6. An electric switch disposed in a housing which in normal use is launched from a craft into the sea from a selected altitude while moving through the atmosphere at a considerable speed, in combination, a bell-crank lever pivoted in the housing so that one arm projects from the housing and the other is disposed in the housing, a stop on the housing, an over-center spring assembly for holding the lever in one end position against the stop, said over-center spring assembly providing a sufficient biasing force that the force of the air on the arm projecting from the housing is not suiiicient to actuate the lever but having a biasing force that is far insuiiicient to prevent operation of the lever by the impact of the sea water against the lever projecting from the housing when the housing strikes the sea, and switching means operated by the operation of the lever, a breakable coupling between the housing and lever for holding the lever against the stop but which breaks when the housing strikes the sea and the sea water acts on the arm projecting from the housing, latching means normally locking said lever against said stop, said latching means being operable to unlatch the lever when the housing upon launching has moved a given distance from the launching craft.

'7. An electric switch, comprising, in combination, a sealed housing for preventing the medium about the housing from leaking into the housing, a leakproof bearing in a wall of said housing, an oi-set bell-crank lever having one arm disposed at the outside of the housing, having a shaft portion disposed through said bearing, and another arm on the inside of the housing, switching means in the housing operable by operation of said lever from one end position to another end position, a spring secured to the arm in the housing and to the housing for biasing said lever to the rst end position, said spring being so connected to the arm in the housing and the housing that an over-center bias is placed on the lever, said housing in normal use is launched from an aircraft into the sea, whereby the impact of the sea water on the lever projecting from the housing operates the lever to the other end position.

8. An electric switch, comprising, in combination, a sealed housing for preventing the medium about the housing from leaking into the housing, a leakproof bearing in a wall of said housing, an off-set bell-crank lever having one arm disposed at the outside of the housing, having a shaft portion disposed through said bearing, and another arm on the inside of the housing, switching means in thehousing operable by operation of said lever from one end position to another end position, a spring secured to the arm in the housing and to the housingI for biasing saidv lever to the rst end position, said spring being so connected to the arm in the housing and the housing that an overcenter bias is placed on the lever, said housing in normal use is launched from an aircraft into the sea, whereby the impact of the sea water on the lever projecting from the housing operates the lever Vto the other end position, afrangible coupling between the lever and the housing for holding the lever in its iirst end position, the strength of the coupling-being sumcent to prevent the force of the air from operating the lever after Y launching of the housing but being insufficient to hold the lever when acted upon by the sea water impact.

9. An electric switch, comprising, in combination, a sealed housing for preventing the medium about the housing from leaking into the housing, a leakproof bearing in a wall of said housing, an off-set bell-crank lever having one arm disposed at the outside of the housing, having a shaft portion disposed through said bearing, and another arm on the inside of the housing, switching means inthe housing operable by operation of said lever from one end position to another end position, a spring secured to the arm in the housing and to the housing for biasing said lever to the i'lrst end position, said spring being so connected to the arm in the housing and the housing that an over-center bias is placed on the lever, said housing in normal use is launched from an aircraft into the sea, whereby the impact of the sea water on the lever projecting from the housing operates the lever to the other end position, removable latching means for said lever for latching the lever in the first end position, and means for operating said latching means to unlatch the lever when the housing after launching is a given distance from the launching craft.

the housing, a leakproof bearing in a wall of said housing, an off-set bell-crank lever having one arm disposed at the outside of the housing, having a shaft portion disposed through said bearing, and another arm on the inside of the housing, switching means in the housing operable by operation of said lever from one end position to another end position, a spring secured to the arm in the housing and to the housing for biasing said lever to the rst end position, said spring being so connected to the arm in the housing and the housing that an over-center bias is placed on the lever, said housing in normal use is launched from anaircraft into the sea, whereby the impact of the sea water on the lever projecting from the housing operates the lever to the other end position, a frangible coupling between the lever and the housing for holding the lever in its rst end position, the strength of the coupling being sufcient to prevent the force of the air from operating the lever after launching of the housing but being insuflicient to hold the lever when acted upon by the sea water impact, removable latching means for said lever for latching the lever in the iii-st end position, and means for operating said latching means to unlatch the lever when the housing after launching is va given distance from the launching craft.

11. An electric switch disposed in a housing which in normal use in launched from a craft into the sea from a selected altitude while moving through the atmosphere at a considerable speed, in combination, a bell-crankk lever pivoted in the housing so that one arm projects from the housing and the other is disposed in the housing, a stop on the housing, an overcenter spring assembly for holding the lever in one end position against the stop, said overcenter spring assembly providing asufcient biasing force that the force of the air on the arm projecting from the housing is not suicient to actuate the lever Vbut having a biasing force that is far insufficient to prevent operation of the lever by the impact of the sea Water against the lever projecting from the housing when the housing strikes the sea, and switching means operated by the operation of the lever, latching means normally locking said lever against said stop, a lanyard of a selected length having one end secured to the launching craft and the other end secured to the latching means, whereby said latching means is operable to unlatch the lever when the housing upon launching has moved a given distance from the launching craft.

' ARTHUR V. HUGHES.

LAWRENCE B. RADEMACHER.

No references cited. 

